This invention is concerned with underwater pump installations and is more particularly concerned with apparatus and methods for installing a submergible pump assembly in an underwater wellhead.
World-wide demand for oil and gas has greatly stimulated the drilling and operating of subsea wells. Extensive prior art has therefore evolved with respect to the introduction and installation of equipment in underwater wellheads. See, for example, the following U.S. Pat. Nos.:
______________________________________ Huntsinger et al 3,638,732 Burrus 3,455,114 Petersen 3,604,731 Dean 3,293,867 Ralph et al 3,412,789 Laffont et al 3,511,312 Morrill 3,741,294 Culver et al 3,101,118 Johnstone et al 3,285,337 Yetman 3,312,282 Brown 3,605,884 Herd 3,678,996 Wakefield, Jr. 3,662,822 Delacour et al 3,538,238 Talley, Jr. 3,638,722 ______________________________________
One of the problems treated in the prior art is the installation of a submergible pump assembly in an underwater wellhead. Various techniques have been proposed. For example, in the aforesaid U.S. Pat. No. 3,638,732, the pump assembly is suspended by cable from the underwater production tree, but the establishment of electrical connections to the pump assembly requires the services of a diver. In general, prior art techniques for installing submergible pump assemblies in underwater wells suffer from one or more of the following deficiencies: complexity, high cost, inefficiency, unreliability, exposure of the pump assembly to damage, insecure mounting and inadequate sealing of the pump assembly in the wellhead, and exposure of the installation apparatus to sea water.